Glenys Stacey came under fire after it was revealed GCSE grading problems were identified three years ago, but Ofqual failed to act. The watchdog has vowed to fight the High Court battle but during a commons select committee grilling, Stacey admitted communication "could have been better".

Mike Griffiths, president of the Association of School and College Leaders, said re-sits are "not the answer".

Griffiths, who forms part of the alliance challenging Ofqual in court, said: "Let’s not forget the tens of thousands of students who had their hopes raised by these resits only to have them dashed again."